Approximately 7 million Americans currently use hearing aid devices to help improve their hearing and speech comprehension abilities. While the batteries used to power the hearing aid devices are inexpensive, safe to use, and easy to dispose of, most non-chargeable batteries are only operational for approximately one week before the batteries are completely depleted and need to be replaced with a new set of batteries.
In other instances, hearing aid devices may also utilize rechargeable batteries, such as lithium ion rechargeable batteries by way of example. While lithium ion rechargeable batteries may be an attractive form of a reusable energy storage system due to its high specific energy and energy density, they are not without drawbacks. For example, lithium ion rechargeable batteries develop increased internal resistance over time, which decreases the rechargeable battery's ability to hold and deliver current to the portable electronic devices. This results in the need to more frequently recharge the lithium ion rechargeable batteries, which not only creates great inconvenience to the device user, but may even potentially create life threatening situations when the rechargeable batteries are used to power portable medical devices. This is especially true since senior members often constitute the largest group of members who regularly use portable medical devices on a daily basis, where the portable medical devices may even be often used to treat and manage potentially life threatening medical conditions.
As such, increasing the amount of energy or charge that can be packed into a given volume of rechargeable batteries is one of the major challenges in improving the advantages of lithium ion rechargeable batteries over other competing energy storage types. By doing so, the need to constantly or frequently recharge the lithium ion rechargeable battery is effectively eliminated, which then results in increased efficiency, battery life, and dependability.
However, it should be noted that the problems associated with non-chargeable batteries and rechargeable batteries are not strictly limited to hearings aids or other medical advices, but rather, also applies to all battery powered devices in general.